<?php  if ( ! defined('BASE_PATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 4.3.2 or newer
 *
 * @package		CodeIgniter
 * @author		ExpressionEngine Dev Team
 * @copyright	Copyright (c) 2008, EllisLab, Inc.
 * @license		http://codeigniter.com/user_guide/license.html
 * @link		http://codeigniter.com
 * @since		Version 1.0
 * @filesource
 */

// ------------------------------------------------------------------------

/**
 * Zip Compression Class
 *
 * This class is based on a library I found at Zend:
 * http://www.zend.com/codex.php?id=696&single=1
 *
 * The original library is a little rough around the edges so I
 * refactored it and added several additional methods -- Rick Ellis
 *
 * @package		CodeIgniter
 * @subpackage	Libraries
 * @category	Encryption
 * @author		ExpressionEngine Dev Team
 * @link		http://codeigniter.com/user_guide/libraries/zip.html
 */
class CI_Zip {

    var $zipdata 	= '';
    var $directory 	= '';
    var $entries 	= 0;
    var $file_num 	= 0;
    var $offset		= 0;

    function CI_Zip() {
        log_message('debug', "Zip Compression Class Initialized");
    }

    // --------------------------------------------------------------------

    /**
     * Add Directory
     *
     * Lets you add a virtual directory into which you can place files.
     *
     * @access	public
     * @param	mixed	the directory name. Can be string or array
     * @return	void
     */
    function add_dir($directory) {
        foreach ((array)$directory as $dir) {
            if ( ! preg_match("|.+/$|", $dir)) {
                $dir .= '/';
            }

            $this->_add_dir($dir);
        }
    }

    // --------------------------------------------------------------------

    /**
     * Add Directory
     *
     * @access	private
     * @param	string	the directory name
     * @return	void
     */
    function _add_dir($dir) {
        $dir = str_replace("\\", "/", $dir);

        $this->zipdata .=
                "\x50\x4b\x03\x04\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00"
                .pack('V', 0) // crc32
                .pack('V', 0) // compressed filesize
                .pack('V', 0) // uncompressed filesize
                .pack('v', strlen($dir)) // length of pathname
                .pack('v', 0) // extra field length
                .$dir
                // below is "data descriptor" segment
                .pack('V', 0) // crc32
                .pack('V', 0) // compressed filesize
                .pack('V', 0); // uncompressed filesize

        $this->directory .=
                "\x50\x4b\x01\x02\x00\x00\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00"
                .pack('V',0) // crc32
                .pack('V',0) // compressed filesize
                .pack('V',0) // uncompressed filesize
                .pack('v', strlen($dir)) // length of pathname
                .pack('v', 0) // extra field length
                .pack('v', 0) // file comment length
                .pack('v', 0) // disk number start
                .pack('v', 0) // internal file attributes
                .pack('V', 16) // external file attributes - 'directory' bit set
                .pack('V', $this->offset) // relative offset of local header
                .$dir;

        $this->offset = strlen($this->zipdata);
        $this->entries++;
    }

    // --------------------------------------------------------------------

    /**
     * Add Data to Zip
     *
     * Lets you add files to the archive. If the path is included
     * in the filename it will be placed within a directory.  Make
     * sure you use add_dir() first to create the folder.
     *
     * @access	public
     * @param	mixed
     * @param	string
     * @return	void
     */
    function add_data($filepath, $data = NULL) {
        if (is_array($filepath)) {
            foreach ($filepath as $path => $data) {
                $this->_add_data($path, $data);
            }
        }
        else {
            $this->_add_data($filepath, $data);
        }
    }

    // --------------------------------------------------------------------

    /**
     * Add Data to Zip
     *
     * @access	private
     * @param	string	the file name/path
     * @param	string	the data to be encoded
     * @return	void
     */
    function _add_data($filepath, $data) {
        $filepath = str_replace("\\", "/", $filepath);

        $uncompressed_size = strlen($data);
        $crc32  = crc32($data);

        $gzdata = gzcompress($data);
        $gzdata = substr($gzdata, 2, -4);
        $compressed_size = strlen($gzdata);

        $this->zipdata .=
                "\x50\x4b\x03\x04\x14\x00\x00\x00\x08\x00\x00\x00\x00\x00"
                .pack('V', $crc32)
                .pack('V', $compressed_size)
                .pack('V', $uncompressed_size)
                .pack('v', strlen($filepath)) // length of filename
                .pack('v', 0) // extra field length
                .$filepath
                .$gzdata; // "file data" segment

        $this->directory .=
                "\x50\x4b\x01\x02\x00\x00\x14\x00\x00\x00\x08\x00\x00\x00\x00\x00"
                .pack('V', $crc32)
                .pack('V', $compressed_size)
                .pack('V', $uncompressed_size)
                .pack('v', strlen($filepath)) // length of filename
                .pack('v', 0) // extra field length
                .pack('v', 0) // file comment length
                .pack('v', 0) // disk number start
                .pack('v', 0) // internal file attributes
                .pack('V', 32) // external file attributes - 'archive' bit set
                .pack('V', $this->offset) // relative offset of local header
                .$filepath;

        $this->offset = strlen($this->zipdata);
        $this->entries++;
        $this->file_num++;
    }

    // --------------------------------------------------------------------

    /**
     * Read the contents of a file and add it to the zip
     *
     * @access	public
     * @return	bool
     */
    function read_file($path, $preserve_filepath = FALSE) {
        if ( ! file_exists($path)) {
            return FALSE;
        }

        if (FALSE !== ($data = file_get_contents($path))) {
            $name = str_replace("\\", "/", $path);

            if ($preserve_filepath === FALSE) {
                $name = preg_replace("|.*/(.+)|", "\\1", $name);
            }

            $this->add_data($name, $data);
            return TRUE;
        }
        return FALSE;
    }

    // ------------------------------------------------------------------------

    /**
     * Read a directory and add it to the zip.
     *
     * This function recursively reads a folder and everything it contains (including
     * sub-folders) and creates a zip based on it.  Whatever directory structure
     * is in the original file path will be recreated in the zip file.
     *
     * @access	public
     * @param	string	path to source
     * @return	bool
     */
    function read_dir($path) {
        if ($fp = @opendir($path)) {
            while (FALSE !== ($file = readdir($fp))) {
                if (@is_dir($path.$file) && substr($file, 0, 1) != '.') {
                    $this->read_dir($path.$file."/");
                }
                elseif (substr($file, 0, 1) != ".") {
                    if (FALSE !== ($data = file_get_contents($path.$file))) {
                        $this->add_data(str_replace("\\", "/", $path).$file, $data);
                    }
                }
            }
            return TRUE;
        }
    }

    // --------------------------------------------------------------------

    /**
     * Get the Zip file
     *
     * @access	public
     * @return	binary string
     */
    function get_zip() {
        // Is there any data to return?
        if ($this->entries == 0) {
            return FALSE;
        }

        $zip_data = $this->zipdata;
        $zip_data .= $this->directory."\x50\x4b\x05\x06\x00\x00\x00\x00";
        $zip_data .= pack('v', $this->entries); // total # of entries "on this disk"
        $zip_data .= pack('v', $this->entries); // total # of entries overall
        $zip_data .= pack('V', strlen($this->directory)); // size of central dir
        $zip_data .= pack('V', strlen($this->zipdata)); // offset to start of central dir
        $zip_data .= "\x00\x00"; // .zip file comment length

        return $zip_data;
    }

    // --------------------------------------------------------------------

    /**
     * Write File to the specified directory
     *
     * Lets you write a file
     *
     * @access	public
     * @param	string	the file name
     * @return	bool
     */
    function archive($filepath) {
        if ( ! ($fp = @fopen($filepath, FOPEN_WRITE_CREATE_DESTRUCTIVE))) {
            return FALSE;
        }

        flock($fp, LOCK_EX);
        fwrite($fp, $this->get_zip());
        flock($fp, LOCK_UN);
        fclose($fp);

        return TRUE;
    }

    // --------------------------------------------------------------------

    /**
     * Download
     *
     * @access	public
     * @param	string	the file name
     * @param	string	the data to be encoded
     * @return	bool
     */
    function download($filename = 'backup.zip') {
        if ( ! preg_match("|.+?\.zip$|", $filename)) {
            $filename .= '.zip';
        }

        $zip_content =& $this->get_zip();

        $CI =& get_instance();
        $CI->load->helper('download');

        force_download($filename, $zip_content);
    }

    // --------------------------------------------------------------------

    /**
     * Initialize Data
     *
     * Lets you clear current zip data.  Useful if you need to create
     * multiple zips with different data.
     *
     * @access	public
     * @return	void
     */
    function clear_data() {
        $this->zipdata		= '';
        $this->directory	= '';
        $this->entries		= 0;
        $this->file_num		= 0;
        $this->offset		= 0;
    }

}
